One option is to make your own custom boards by downloading https://kicad.org and learn how to use it to modify the board yourself.
The title of this thread references Lithium Iron Phosphate (LiFePo4) batteries but
contains the text LTO.
Isn’t LTO a reference to Lithium Titanate Oxide?
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yeah, that was a typo, and I can’t edit it. 
No problem. I fixed it for you.
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LiFePO4
@Michaelillingby, I made a board for the prismatic LiFePO4 cells cause im using Lishen 272Ah cells (also 89mm spacing with M6 screws) for my next project. The modules are on the way to me assembled from JLC. As soon as i know them working i will release my version of the DIYBMS v4 PCB.
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that looks awesome.
I have questions…
first, that mosfet looks huge, did you do that to allow for higher discharge current? if so how much? what are the specs on this ?
Those M6 Vias look great too. could you share those files with me so I could take a look at what you’ve done?
Love the layout, it was exactly what I had in mind.
It would be great if there were some 3 inch jst plugs premade twisted etc.
thanks for doing this, again they look great!
When do you expect to receive them?
First i planed with an SOT8 mosfet but they are more expensive and i have still some some TO-252 mosfet laying around. The board is now planed with up to 4A discharge current thats also the reason why I’m not using the original mosfet form Stuarts design anymore. Now the biggest question for me is if the PCB can transfer the heat away from the resistors fast enough. Maybe i will also add a different version with the possibility of an external resistor.
The PCB should hopefully arrive in the next few days.
You can have a look in my EASYEDA libary: DIYBMS_Prismatic - EasyEDA open source hardware lab
Comments on the schematic are still the originals from Stuart so they are not correct for my design 
as i said work in progress 
If heat dissipation is a problem, maybe a new layout with all the resistors grouped together so that a heatsink can be fitted.
My idea was to mount the PCB upside down and fit a Heat sink on the Backside of the PCB. Hopefully my cells are well enough grouped by resistance and i don’t think i will ever need the balancing. I’m only going to charge the bank to 3.45V per cell.
I guess that could work, but then we can’t see all the pretty blinking lights 
I guess then it would be a larger heatsink as well then, any idea on the part you would use and the cost? I for instance would require 34 of these heatsinks right now, more when I expand so that cost increases.
I also assume that with PWM modulation, the heat can be managed.
What is the purpose of the ± connections near the middle of the board?
You mean the connector next to the ISP? That is an JST XH socket for the external Temp resistor.
I did not choose an heatsink until now because i dont know if im goning to need them. As i know the firmware from Stuard includes PWM for the balancing circuit. Topbalancing of 280Ah LiFePO4 cells is quite difficult and i just will use the balancing function to equalize the cells from time to time.
how did your boards turn out? did you have them do the assebmly at the factory? i’d love an update as I really want to redo my system with a cleaner setup
Boards arrived yesterday. First impression they looking good. Haven’t had time to check them until now.
I will post some pics tomorrow or the next few days
i can’t hardly wait. My setup is working, but the wiring looks pretty messy if i’m being honest.
@Jau I also have some new 272Ah Lishen cells and would like to use your version so please let us know how your modification is working 
any updates on these new boards?
Sorry @all, had problems with our central heating system in the last few days. Had higher priority to fix that first. I will have a look for the PCB the next few days